[][mt7988][add bananapi bpi-r4 device tree support]

[Description]
Add bananapi bpi-r4 device tree support

[Release-log]
N/A


Change-Id: Ic2973dbf9c162e3bc8ad09fa1c5d77c41b3c419d
Reviewed-on: https://gerrit.mediatek.inc/c/openwrt/feeds/mtk_openwrt_feeds/+/8858608
3 files changed